The authors report experimental evidence for an enhanced density of states at the Fermi level in Al86Mn14 and Al75Mn20Si5 quasicrystals (QC) as indicated by the low-temperature specific heat and resistivity. The excess specific-heat term Δγ is proportional to the Mn concentration in these QC samples as is the case for dilute AlMn alloys. Spin-glass-like behavior is observed in both QC samples. In Al-Mn-Si, the relative frequency dependence of the AC susceptibility cusp is comparable to canonical spin glasses such as AgMn or CuMn